Monitoring Quakes

Vocabulary

Outline

Devices that can Monitor Faults

• Scientists make instruments to measure stress and deformation
• No one can predict earthquakes, only get an idea of it's arrival

• Measures horizontal movement
• Measures how much weight moved against measuring scale
  • uses wire attached to anchor post on one side, weight on the other side
  • when fault moves, it triggers wire and wire triggers weight.
    • weight movement then gets recorded on measuring scale

• beam reflects off reflector and comes back
• scientists check if it takes longer for beam to return
  • if so, there is plate movement

• Measures when ground tilts
• two bulbs connected by a hollow tube
  • water travels from one bulb, through the tube, and to the other bulb when plate moves
    • scientists look at scales on bulb to see fault movement

• Sends sound waves to fault, they bounce back.
  • scientists check the difference between the time it bounces back

Monitoring Risk in the United States

• Locate where faults are active
• Locate where earthquakes have already happened